Methods And Apparatus For Automatically Recording Push-To-Talk (PTT) Voice Communications For Replay

ABSTRACT

In one illustrative example, a mobile station includes a wireless transceiver which operates with a wireless communication network; a processor; memory coupled to the processor; and a user interface which includes a Push-To-Talk (PTT) switch for transmitting a PTT voice communication through the wireless transceiver, a PTT replay switch for replaying a PTT voice communication previously received through the wireless transceiver which is stored in the memory, and a speaker for outputting audible voice signals. The wireless transceiver is operative to receive a PTT key message; receive voice data of a PTT voice communication following the PTT key message; and receive a PTT dekey message following the voice data. The processor is operative to cause the voice data of the PTT voice communication to be recorded in the memory based on receiving the PTT key message, and cause the recording of voice data of the PTT voice communication to be terminated based on receiving the PTT dekey message. Subsequently, in response to detecting a user actuation of the PTT replay switch, the processor causes the voice data of the PTT voice communication to be retrieved from the memory and audible voice signals corresponding to the voice data to be output from the speaker.

CROSS-REFERENCED TO RELATED APPLICATION

This application is a continuation application of U.S. patentapplication having application Ser. No. 10/883,266 and filing date ofJun. 30, 2004 entitled “Methods And Apparatus for AutomaticallyRecording Push-To-Talk (PTT) Voice Communications For Reply,” now U.S.Patent No. ______, which is hereby incorporated by reference herein.

BACKGROUND

1. Field of the Technology

The present disclosure relates generally to Push-To-Talk (PTT) voicecommunications, and more particularly to methods and apparatus forrecording and replaying PTT voice communications in a mobile station.

2. Description of the Related Art

A wireless communication device, such as a cellular telephone or mobilestation, is capable of making and receiving voice calls and/or sendingand receiving data over a wireless communication network. Some networksoffer mobile stations the ability to communicate in “push-to-talk” (PTT)modes. One example of a wireless network that provides for PTTcommunications is an iDEN network. Other networks utilize Push-to-talkover Cellular (PoC) technology. PoC communication utilizes Voice-over-IP(VoIP) techniques which involve the communication of data packetscarrying voice data.

PTT voice communications are different from traditional cellulartelephony communications in that the voice communications are generallyimmediate and unannounced. An end user of the mobile station may be busyor caught “off-guard” and not listening to the initial communication.Thus, the end user may not hear at least the initial PTT voicecommunication. This is inconvenient and often wasteful of bandwidthresources, as the talk groups may have to respond to indicate that theydid not hear the initial PTT communication.

Accordingly, there is a resulting need for mobile station methods andapparatus to overcome the deficiencies of the prior art.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of present disclosure will now be described by way ofexample with reference to attached figures, wherein:

FIG. 1 is a block diagram which illustrates pertinent components of amobile station and a wireless communication network;

FIG. 2 is a more detailed diagram of a preferred mobile station of FIG.1;

FIG. 3 is a block diagram of system components pertaining to PoCcommunication sessions;

FIG. 4 is a schematic block diagram of pertinent electrical componentsfor the automatic recording of PTT voice communications for replay inthe mobile station of FIGS. 1-2;

FIG. 5 is an illustrative representation of a circular buffer memory ofthe schematic block diagram of FIG. 4;

FIG. 6 is a flowchart for describing a method of automatically recordingPTT voice communications for replay in a mobile station;

FIG. 7 is a flowchart for describing a method of providing replay of thepreviously recorded PTT voice communications in the mobile station;

FIG. 8 is an exemplary illustration of a mobile station showing a userinterface for replaying the previously recorded PTT voicecommunications;

FIG. 9 is a plan view of a scrollwheel that may be utilized forreplaying PTT voice communications; and

FIG. 10 is a side view of the scrollwheel of FIG. 9.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Methods and apparatus for automatically recording Push-To-Talk (PTT)voice communications for replay in a mobile station are describedherein. In one illustrative example, a mobile station includes awireless transceiver which operates with a wireless communicationnetwork; a processor; memory coupled to the processor; and a userinterface which includes a Push-To-Talk (PTT) switch for transmitting aPTT voice communication through the wireless transceiver, a PTT replayswitch for replaying a PTT voice communication previously receivedthrough the wireless transceiver which is stored in the memory, and aspeaker for outputting audible voice signals. The wireless transceiveris operative to receive a PTT key message; receive voice data of a PTTvoice communication following the PTT key message; and receive a PTTdekey message following the voice data. The processor is operative tocause the voice data of the PTT voice communication to be recorded inthe memory based on receiving the PTT key message, and cause therecording of voice data of the PTT voice communication to be terminatedbased on receiving the PTT dekey message. Subsequently, in response todetecting a user actuation of the PTT replay switch, the processorcauses the voice data of the PTT voice communication to be retrievedfrom the memory and audible voice signals corresponding to the voicedata to be output from the speaker. Advantageously, PTT voicecommunications may be replayed in the event that the end user of themobile station fails to initially hear such communication.

FIG. 1 is a block diagram of a communication system 100 which includes amobile station 102 which communicates through a wireless communicationnetwork 104. Mobile station 102 preferably includes a visual display112, a keyboard 114, and perhaps one or more auxiliary user interfaces(UI) 116, each of which is coupled to a controller 106. Controller 106is also coupled to radio frequency (RF) transceiver circuitry 108 and anantenna 110.

Typically, controller 106 is embodied as a central processing unit (CPU)which runs operating system software in a memory component (not shown).Controller 106 will normally control overall operation of mobile station102, whereas signal processing operations associated with communicationfunctions are typically performed in RF transceiver circuitry 108.Controller 106 interfaces with device display 112 to display receivedinformation, stored information, user inputs, and the like. Keyboard114, which may be a telephone type keypad or full alphanumeric keyboard,is normally provided for entering data for storage in mobile station102, information for transmission to network 104, a telephone number toplace a telephone call, commands to be executed on mobile station 102,and possibly other or different user inputs.

Mobile station 102 sends communication signals to and receivescommunication signals from network 104 over a wireless link via antenna110. RF transceiver circuitry 108 performs functions similar to those ofa radio network (RN) 128, including for example modulation/demodulationand possibly encoding/decoding and encryption/decryption. It is alsocontemplated that RF transceiver circuitry 108 may perform certainfunctions in addition to those performed by RN 128. It will be apparentto those skilled in art that RF transceiver circuitry 108 will beadapted to particular wireless network or networks in which mobilestation 102 is intended to operate.

Mobile station 102 includes a battery interface 122 for receiving one ormore rechargeable batteries 124. Battery 124 provides electrical powerto electrical circuitry in mobile station 102, and battery interface 122provides for a mechanical and electrical connection for battery 124.Battery interface 122 is coupled to a regulator 126 which regulatespower to the device. When mobile station 102 is fully operational, an RFtransmitter of RF transceiver circuitry 108 is typically turned on onlywhen it is sending to network, and is otherwise turned off to conserveresources. Similarly, an RF receiver of RF transceiver circuitry 108 istypically periodically turned off to conserve power until it is neededto receive signals or information (if at all) during designated timeperiods.

Mobile station 102 operates using a memory module 120, such as aSubscriber Identity Module (SIM) or a Removable User Identity Module(R-UIM), which is connected to or inserted in mobile station 102 at aninterface 118. As an alternative to a SIM or an R-UIM, mobile station102 may operate based on configuration data programmed by a serviceprovider into an internal memory which is a non-volatile memory. Mobilestation 102 may consist of a single unit, such as a data communicationdevice, a cellular telephone, a multiple-function communication devicewith data and voice communication capabilities, a personal digitalassistant (PDA) enabled for wireless communication, or a computerincorporating an internal modem. Alternatively, mobile station 102 maybe a multiple-module unit comprising a plurality of separate components,including but in no way limited to a computer or other device connectedto a wireless modem. In particular, for example, in the mobile stationblock diagram of FIG. 1, RF transceiver circuitry 108 and antenna 110may be implemented as a radio modem unit that may be inserted into aport on a laptop computer. In this case, the laptop computer wouldinclude display 112, keyboard 114, and one or more auxiliary UIs 116,and controller 106 may remain within the radio modem unit thatcommunicates with the computer's CPU or be embodied as the computer'sCPU. It is also contemplated that a computer or other equipment notnormally capable of wireless communication may be adapted to connect toand effectively assume control of RF transceiver circuitry 108 andantenna 110 of a single-unit device such as one of those describedabove. Such a mobile station 102 may have a more particularimplementation as described later in relation to mobile station 202 ofFIG. 2.

Mobile station 102 communicates in and through wireless communicationnetwork 104, which is preferably a cellular telecommunications network.In the embodiment of FIG. 1, wireless network 104 is a Third Generation(3G) supported network based on Code Division Multiple Access (CDMA)technologies. In particular, wireless network 104 is a CDMA2000 networkwhich includes fixed network components coupled as shown in FIG. 1.Wireless network 104 of the CDMA2000-type includes a Radio Network (RN)128, a Mobile Switching Center (MSC) 130, a Signaling System 7 (SS7)network 140, a Home Location Register/Authentication Center (HLR/AC)138, a Packet Data Serving Node (PDSN) 132, an IP network 134, and aRemote Authentication Dial-In User Service (RADIUS) server 136. SS7network 140 is communicatively coupled to a network 142 (such as aPublic Switched Telephone Network or PSTN), whereas IP network iscommunicatively coupled to a network 144 (such as the Internet).

During operation, mobile station 102 communicates with RN 128 whichperforms functions such as call-setup, call processing, and mobilitymanagement. RN 128 includes a plurality of base station transceiversystems that provide wireless network coverage for a particular coveragearea commonly referred to as a “cell”. A given base station transceiversystem of RN 128, such as the one shown in FIG. 1, transmitscommunication signals to and receives communication signals from mobilestations within its cell. The base station transceiver system normallyperforms such functions as modulation and possibly encoding and/orencryption of signals to be transmitted to the mobile station inaccordance with particular, usually predetermined, communicationprotocols and parameters, under control of its controller. The basestation transceiver system similarly demodulates and possibly decodesand decrypts, if necessary, any communication signals received frommobile station 102 within its cell. Communication protocols andparameters may vary between different networks. For example, one networkmay employ a different modulation scheme and operate at differentfrequencies than other networks. The underlying services may also differbased on its particular protocol revision.

The wireless link shown in communication system 100 of FIG. 1 representsone or more different channels, typically different radio frequency (RF)channels, and associated protocols used between wireless network 104 andmobile station 102. An RF channel is a limited resource that must beconserved, typically due to limits in overall bandwidth and a limitedbattery power of mobile station 102. Those skilled in art willappreciate that a wireless network in actual practice may includehundreds of cells depending upon desired overall expanse of networkcoverage. All pertinent components may be connected by multiple switchesand routers (not shown), controlled by multiple network controllers.

For all mobile stations 102 registered with a network operator,permanent data (such as mobile station 102 user's profile) as well astemporary data (such as mobile station's 102 current location) arestored in a HLR/AC 138. In case of a voice call to mobile station 102,HLR/AC 138 is queried to determine the current location of mobilestation 102. A Visitor Location Register (VLR) of MSC 130 is responsiblefor a group of location areas and stores the data of those mobilestations that are currently in its area of responsibility. This includesparts of the permanent mobile station data that have been transmittedfrom HLR/AC 138 to the VLR for faster access. However, the VLR of MSC130 may also assign and store local data, such as temporaryidentifications. Mobile station 102 is also authenticated on systemaccess by HLR/AC 138. In order to provide packet data services to mobilestation 102 in a CDMA2000-based network, RN 128 communicates with PDSN132. PDSN 132 provides access to the Internet 144 (or intranets,Wireless Application Protocol (WAP) servers, etc.) through IP network134. PDSN 132 also provides foreign agent (FA) functionality in mobileIP networks as well as packet transport for virtual private networking.PDSN 132 has a range of IP addresses and performs IP address management,session maintenance, and optional caching. RADIUS server 136 isresponsible for performing functions related to authentication,authorization, and accounting (AAA) of packet data services, and may bereferred to as an AAA server.

Wireless communication network 104 also includes a Push-to-talk overCellular (PoC) server 137 which may be coupled to IP network 134. PoCserver 137 operates to facilitate PoC individual and group communicationsessions between mobile stations within network 104. A conventional PoCcommunication session involves a session connection between end users ofmobile stations, referred to as session “participants”, who communicateone at a time in a half-duplex manner much like conventionalwalkie-talkies or two-way radios.

Those skilled in art will appreciate that wireless network 104 may beconnected to other systems, possibly including other networks, notexplicitly shown in FIG. 1. Although a CDMA network has been describedas the environment, other suitable networks may be utilized, such asGlobal System for Mobile communications (GSM) and General Packet RadioService (GPRS) network.

FIG. 2 is a detailed block diagram of a preferred mobile station 202.Mobile station 202 is preferably a two-way communication device havingat least voice and advanced data communication capabilities, includingthe capability to communicate with other computer systems. Depending onthe functionality provided by mobile station 202, it may be referred toas a data messaging device, a two-way pager, a cellular telephone withdata messaging capabilities, a wireless Internet appliance, or a datacommunication device (with or without telephony capabilities). Mobilestation 202 may communicate with any one of a plurality of base stationtransceiver systems 200 within its geographic coverage area. Mobilestation 202 selects or helps select which one of base stationtransceiver systems 200 it will communicate with, as will be describedin more detail later in relation to FIGS. 3 and 4.

Mobile station 202 will normally incorporate a communication subsystem211, which includes a receiver 212, a transmitter 214, and associatedcomponents, such as one or more (preferably embedded or internal)antenna elements 216 and 218, local oscillators (LOs) 213, and aprocessing module such as a digital signal processor (DSP) 220.Communication subsystem 211 is analogous to RF transceiver circuitry 108and antenna 110 shown in FIG. 1. As will be apparent to those skilled infield of communications, particular design of communication subsystem211 depends on the communication network in which mobile station 202 isintended to operate.

Mobile station 202 may send and receive communication signals over thenetwork after required network registration or activation procedureshave been completed. Signals received by antenna 216 through the networkare input to receiver 212, which may perform such common receiverfunctions as signal amplification, frequency down conversion, filtering,channel selection, and like, and in example shown in FIG. 2,analog-to-digital (A/D) conversion. A/D conversion of a received signalallows more complex communication functions such as demodulation anddecoding to be performed in DSP 220. In a similar manner, signals to betransmitted are processed, including modulation and encoding, forexample, by DSP 220. These DSP-processed signals are input totransmitter 214 for digital-to-analog (D/A) conversion, frequency upconversion, filtering, amplification and transmission over communicationnetwork via antenna 218. DSP 220 not only processes communicationsignals, but also provides for receiver and transmitter control. Forexample, the gains applied to communication signals in receiver 212 andtransmitter 214 may be adaptively controlled through automatic gaincontrol algorithms implemented in DSP 220.

Network access is associated with a subscriber or user of mobile station202, and therefore mobile station 202 requires a memory module 262, suchas a Subscriber Identity Module or “SIM” card or a Removable UserIdentity Module (R-UIM), to be inserted in or connected to an interface264 of mobile station 202 in order to operate in the network.Alternatively, memory module 262 may be a non-volatile memory which isprogrammed with configuration data by a service provider so that mobilestation 202 may operate in the network. Since mobile station 202 is amobile battery-powered device, it also includes a battery interface 254for receiving one or more rechargeable batteries 256. Such a battery 256provides electrical power to most if not all electrical circuitry inmobile station 202, and battery interface 254 provides for a mechanicaland electrical connection for it. The battery interface 254 is coupledto a regulator (not shown in FIG. 2) which provides power V+ to all ofthe circuitry.

Mobile station 202 includes a microprocessor 238 (which is oneimplementation of controller 106 of FIG. 1) which controls overalloperation of mobile station 202. This control includes network selectiontechniques of the present application. Communication functions,including at least data and voice communications, are performed throughcommunication subsystem 211.

Microprocessor 238 also interacts with additional device subsystems suchas a display 222, a flash memory 224, a random access memory (RAM) 226,auxiliary input/output (I/O) subsystems 228, a serial port 230, akeyboard 232, a speaker 234, a microphone 236, a short-rangecommunications subsystem 240, and any other device subsystems generallydesignated at 242. Some of the subsystems shown in FIG. 2 performcommunication-related functions, whereas other subsystems may provide“resident” or on-device functions. Notably, some subsystems, such askeyboard 232 and display 222, for example, may be used for bothcommunication-related functions, such as entering a text message fortransmission over a communication network, and device-resident functionssuch as a calculator or task list. Operating system software used bymicroprocessor 238 is preferably stored in a persistent store such asflash memory 224, which may alternatively be a read-only memory (ROM) orsimilar storage element (not shown). Those skilled in the art willappreciate that the operating system, specific device applications, orparts thereof, may be temporarily loaded into a volatile store such asRAM 226.

Microprocessor 238, in addition to its operating system functions,preferably enables execution of software applications on mobile station202. A predetermined set of applications which control basic deviceoperations, including at least data and voice communicationapplications, will normally be installed on mobile station 202 duringits manufacture. A preferred application that may be loaded onto mobilestation 202 may be a personal information manager (PIM) applicationhaving the ability to organize and manage data items relating to usersuch as, but not limited to, e-mail, calendar events, voice mails,appointments, and task items. Naturally, one or more memory stores areavailable on mobile station 202 and SIM 256 to facilitate storage of PIMdata items and other information.

The PIM application preferably has the ability to send and receive dataitems via the wireless network. In a preferred embodiment, PIM dataitems are seamlessly integrated, synchronized, and updated via thewireless network, with the mobile station user's corresponding dataitems stored and/or associated with a host computer system therebycreating a mirrored host computer on mobile station 202 with respect tosuch items. This is especially advantageous where the host computersystem is the mobile station user's office computer system. Additionalapplications may also be loaded onto mobile station 202 through network,an auxiliary I/O subsystem 228, serial port 230, short-rangecommunications subsystem 240, or any other suitable subsystem 242, andinstalled by a user in RAM 226 or preferably a non-volatile store (notshown) for execution by microprocessor 238. Such flexibility inapplication installation increases the functionality of mobile station202 and may provide enhanced on-device functions, communication-relatedfunctions, or both. For example, secure communication applications mayenable electronic commerce functions and other such financialtransactions to be performed using mobile station 202.

In a data communication mode, a received signal such as a text message,an e-mail message, or web page download will be processed bycommunication subsystem 211 and input to microprocessor 238.Microprocessor 238 will preferably further process the signal for outputto display 222 or alternatively to auxiliary I/O device 228. A user ofmobile station 202 may also compose data items, such as e-mail messages,for example, using keyboard 232 in conjunction with display 222 andpossibly auxiliary I/O device 228. Keyboard 232 is preferably a completealphanumeric keyboard and/or telephone-type keypad. These composed itemsmay be transmitted over a communication network through communicationsubsystem 211.

For voice communications, the overall operation of mobile station 202 issubstantially similar, except that the received signals would be outputto speaker 234 and signals for transmission would be generated bymicrophone 236. Alternative voice or audio I/O subsystems, such as avoice message recording subsystem, may also be implemented on mobilestation 202. Although voice or audio signal output is preferablyaccomplished primarily through speaker 234, display 222 may also be usedto provide an indication of the identity of a calling party, duration ofa voice call, or other voice call related information, as some examples.

Serial port 230 in FIG. 2 is normally implemented in a personal digitalassistant (PDA)-type communication device for which synchronization witha user's desktop computer is a desirable, albeit optional, component.Serial port 230 enables a user to set preferences through an externaldevice or software application and extends the capabilities of mobilestation 202 by providing for information or software downloads to mobilestation 202 other than through a wireless communication network. Thealternate download path may, for example, be used to load an encryptionkey onto mobile station 202 through a direct and thus reliable andtrusted connection to thereby provide secure device communication.

Short-range communications subsystem 240 of FIG. 2 is an additionaloptional component which provides for communication between mobilestation 202 and different systems or devices, which need not necessarilybe similar devices. For example, subsystem 240 may include an infrareddevice and associated circuits and components, or a Bluetooth™communication module to provide for communication with similarly-enabledsystems and devices. Bluetooth™ is a registered trademark of BluetoothSIG, Inc.

FIG. 3 is a block diagram of relevant system components 300 pertainingto Push-to-talk over Cellular (PoC) communications, which may beutilized for the present techniques described herein. Alternativenetworks may be utilized just as well, such as an iDEN network. Systemcomponents 300 in FIG. 3 include user equipment (UE) 302 whichrepresents a mobile station, a Push-to-talk over Cellular (PoC) server304, an access 306, a Group and List Management Server (GLMS) 308, an IPMultimedia Subsystem (IMS) core 312, and a presence server 310. Some ofthese components may be optional or not necessary for fundamentaloperation.

A PoC communication session is a session connection between end users ofa UE 302, referred to as session “participants”, who communicate one ata time in a half-duplex manner. PoC communication utilizes Voice over IP(VOIP) technology which involves the communication of data packetscarrying voice information. UE 302 is terminal equipment (e.g. a mobilestation) which includes PoC application client software, which includesfunctionality of the present application but otherwise utilizesconventional techniques. IMS core 312 includes a plurality of SessionInitiation Protocol (SIP) proxies and SIP registrars. The first point ofcontact for UE 302 is one of the proxies in IMS core 312 that isconfigured on UE 302 as the outbound proxy. In the IMS architecture, theoutbound proxy is known as the Proxy-CSCF (P-CSCF). IMS Core 312performs the following functions: (1) routing of SIP signaling betweenUE 302 and PoC server 304; (2) termination of SIP compression from UE302; (3) authentication and authorization; (4) maintenance of theregistration state and the SIP session state; and (5) reporting to thecharging system. UE 302 sends all its SIP messages to the IP address ofthe outbound proxy after resolving the SIP Uniform Resource Identifier(URI) of the outbound proxy to an IP address.

End users use GLMS 308 to manage groups, contact lists, and accesslists. A contact list is a type of address book that may be used by endusers to establish an instant talk session with other PoC users or PoCGroups. An end user may have one or several contact lists includingidentities of other PoC users or PoC groups. Contact list managementincludes operations to allow UE 302 to store and retrieve the contactlists located in GLMS 308. End users can define PoC groups. An end usermay select one group from the list to initiate an instant group talksession or a chat group talk session, depending on the type of group. Anaccess list is used by the end user as a means of controlling who isallowed to initiate instant talk sessions to the end user. An accesslist contains end user defined identities of other end users or groups.The end user may have one blocked identities list and one grantedidentities list.

PoC server 304 includes functionality to perform the PoC service. PoCServer 304 typically performs functions such as: (1) end-point for SIPsignaling; (2) end-point for real-time transport protocol (RTP) and RTPControl Protocol (RTCP) signaling; (3) SIP session handling; (4) policycontrol for access to groups; (5) group session handling; (6) accesscontrol; (7) do-not-disturb functionality; (8) floor controlfunctionality (floor control is a control mechanism that arbitratesrequests, from the UEs, for the right to speak); (9) talkeridentification; (10) participant information; (10) quality feedback;(11) charging reports; and (12) media distribution. Presence server 310manages presence information that is uploaded by presenceuser/network/external agents, and is responsible for combining thepresence-related information for a certain presentity from theinformation it receives from multiple sources into a single presencedocument.

An Is interface supports the communication between UE 302 and IMS core312. This communication includes SIP procedures which support the PoCfeatures.

The protocol for the Is interface is Session Initiation Protocol (SIP).Is signaling is transported on User Datagram Protocol (UDP). Theprotocols over an If interface support the communication between IMScore 312 and PoC server 304 for session control. The protocols over anIt interface support the transport of talk bursts, floor control, andlink quality messages between UE 302 and PoC Server 304. The protocolsover an Im interface support the communication between UE 302 and GLMS308 for the purpose of managing the groups, contact lists and accesslists and Do-not-Disturb indication. HTTP/XML protocols are utilized forthese purposes. The protocols over an Ik interface support thecommunication between PoC Server 304 and GLMS 308, enabling PoC server304 to retrieve the groups and access lists from GLMS 308. The protocolsover an Ips interface enable the uploading of the registration statusfrom IMS core 312 to presence server 310 and the dissemination of thepresence information between presence server 310 and UE 302. Theprotocol over an Ipl interface enables the uploading of Do-not-Disturbstatus and granted/blocked access lists from GLMS 308 to presence server310. The group identity used on the Is interface between the UE and IMScore for group talk is generated by GLMS 308.

Each entity in the PoC system is assigned one or more IP addressesbelonging to public or private IP realms. On the other hand, a end usermay address another user by a phone number. UE 302 sends a phone numberto IMS core 312 in a TEL Uniform Resource Locator (URL). The phonenumber may use the international E.164 format (prefixed with a ‘+’ sign)or a local format using a local dialing plan and prefix. IMS core 312interprets the phone number with a leading ‘+’ to be an E.164 number.Addressing by TEL URL for a PoC session requires that PoC Server 304 canresolve the TEL URL to a SIP URI, for instance by using DNS/ENUM orother local data base. A phone number in a local format is converted tothe E.164 format before DNS/ENUM is used.

End users may initiate PoC talk sessions. An INVITE request on the Isinterface contains an “Accept-Contact” header with a media feature tagindicating the PoC service. IMS core 312 is able to identify the requestas a PoC communication by inspecting the Accept-Contact header. ARequest-URI of the INVITE contains either the pre-configured ad-hocidentity (for instant personal talk and ad-hoc instant group) or a groupidentity (for instant group talk or chat group talk). Early sessionestablishment is used for having a session available for quickconnection establishment using “REFER”. The early sessionestablishment's INVITE does not have any referred party field and can bedifferentiated from this against other INVITEs. A transient groupidentity is generated by PoC server 304 and distributed to UE 302 in the“Contact” header. From an initiating UE 302, the public user identity ofthe inviting user is included in the “From” header. On the signalingtowards the invited user, the “From” header includes either the publicuser identity (instant personal talk, ad-hoc instant group) or the groupidentity (instant group talk or being added to a chat group).

Other than the inventive techniques described herein, the PoCarchitecture and signaling may be the same as is conventional asdescribed in current standard specifications such as Push-to-talk overCellular (PoC), Architecture, PoC Release 1.0—Architecture V1.1.0(2003-08) Technical Specification; and Push-to-talk over Cellular (PoC),Signaling Flows, PoC Release 1.0—Signaling Flows V1.1.3 (2003-08)Technical Specification. In addition, although the PoC architecture andsignaling has been provided as the exemplary environment for thetechniques of the present application, any suitable network andtechniques for PTT voice communications may be utilized. For example,the wireless network may be an iDEN network which provides for PTTcommunications between mobile stations.

FIG. 4 is a schematic block diagram of pertinent electrical components400 of the mobile station of FIGS. 1-2 for automatically recording PTTvoice communications for replay. As shown, electrical components 400include speaker 234, an audio circuit 402, a coder/decoder (CODEC) 404,a voice decompressor 406, a switch 414, a memory 412, a switch 416, achannel decoder and demodulator 408, a receiver 212, processor 238, anda user interface which includes display 222, a PTT communication switch450, and a PTT replay switch 452, all coupled together as shown.Receiver 212 receives RF signals from the wireless network through theantenna. The RF signals may carry a PTT voice communication from anothermobile station. The RF signals are passed to an input of channel decoderand demodulator 408 which decodes and demodulates the signals, tothereby produce compressed voice data.

For telephony communication (e.g. cellular telephone calls), thecompressed voice data is passed to an input of voice decompressor 406which decompresses the incoming data. This decompression step increasesthe data rate of the incoming data. Thus, the data rate at the output ofvoice decompressor 406 (e.g. 64 kbps) is typically substantially higherthan the data rate at the output of channel decoder and demodulator 408(e.g. 8 kbps). Specifically, the digital voice data at the output ofvoice decompressor 406 may be pulse-coded modulated (PCM) data signals.This digital voice data is passed to CODEC 404, which typically includesconventional voice processing circuits such as one or more amplifiers,one or more filters, and a digital-to-analog (D/A) converter. Thus,CODEC 404 converts digital voice data into analog voice signals and hasan output that provides the analog voice signals. The output of CODEC404 is coupled to an input of audio circuit 402, which includescircuitry for biasing, filtering, and amplifying the analog voicesignals. This produces audible voice signals at speaker 234.

Memory 412 is used to store compressed voice data of received PTT voicecommunications, as will be described further herein. A first input ofswitch 414 is coupled to the output of channel coder and demodulator408, a second input of switch 414 is coupled to an output of memory 412,and an output of switch 414 is coupled to the input of voicedecompressor 406. When a switch position “A” is set for switch 414,compressed voice data from channel decoder and demodulator 408 is routedto the input of voice decompressor 406. When a switch position “B” isset for switch 414, compressed voice data from memory 412 is routed tothe input of voice decompressor 406. For recording received PTT voicecommunications, an input of memory 412 is coupled to the output ofchannel decoder and demodulator 418 through switch 416. Switch 416 maybe set to a switch position “D” to couple the output of channel decoderand demodulator 418 to the input of memory 412, or to a switch position“C” which opens the switch so that no compressed voice data is receivedby memory 412.

Processor 238 controls switches 414 and 416 to be in one of threedifferent switch configurations depending on the desired operation. In afirst configuration, processor 238 controls switch 414 to be in switchposition A and switch 416 to be in switch position C for theconventional listening of voice without recording. In a secondconfiguration, processor 238 controls switch 414 to be in switchposition A and switch 416 to be in switch position D for theconventional listening of voice with simultaneous recording in memory412. In a third configuration, processor 238 controls switch 414 to bein switch position B and switch 416 to be in switch position C for thelistening of previously recorded voice from memory 412. This listeningmay be prompted by an actuation of PTT replay switch 452, which may be anormal push-button switch or a switch activated by an insertion of aheadset into the mobile station, for example.

FIG. 5 is an illustrative representation of memory 412 of the schematicblock diagram of FIG. 4. As illustrated, memory 412 which stores voicedata is a circular buffer memory of the First-In-First-Out (FIFO) type.Each square in FIG. 5 represents a separate memory location or blockwhich is separately addressable. Using circular buffering, voice data issaved in a consecutive fashion in memory 412 such that older voice datais written over by newer voice data in a loop-type fashion. Note thatthe size of memory 412 is sufficient to buffer an amount of voice datafor at least one typical PTT voice communication.

A pair of start and end markers 502 and 504 (“markers A”) are used formemory 412 define the boundaries of a single previously-saved PTT voicecommunication. Start marker 502 is used to identify a beginning of thePTT voice communication, and an end marker 504 is used to identify theend of the PTT voice communication. Start and end markers 502 and 504may be in the form of address pointers stored in another portion ofmemory 412 which “point” to the appropriate location in memory 412.Thus, start marker 502 is a pointer address corresponding to a memorylocation of the beginning of the PTT voice communication, and end marker504 is a pointer address corresponding to a memory location of an end ofthe PTT voice communication. Note that more than one PTT voicecommunication can be saved in memory 412 and, therefore, one or moreother pairs of start and end markers 506 and 508 (markers “B”) areprovided for memory 412. Preferably, a plurality of PTT voicecommunications are consecutively saved in memory 412 which havecorresponding pairs of start and end markers for identification andretrieval.

An input pointer 520 in memory 412 identifies a next available memorylocation for saving voice data for a PTT voice communication. On theother hand, an output pointer 508 identifies the next memory locationcorresponding to the voice data of the PTT voice communication to bereplayed. Input and output pointers 520 and 522 may be stored in anotherportion of memory to “point” to the appropriate location within memory412. When voice data of a new PTT voice communication is being saved inmemory 412, input pointer 520 is incremented (or decremented)accordingly to appropriately sequentially read in the voice data fromchannel decoder and demodulator 408 (FIG. 4). On the other hand, whenvoice data of a previously saved PTT voice communication is beingreplayed, output pointer 522 is incremented (or decremented) accordinglyto appropriately sequentially output the voice data of the PTT voicecommunication for processing by voice decompressor 406, CODEC 404, audiocircuit 402, and speaker 234 (FIG. 4).

Referring ahead to FIG. 8, a visual illustration of a front side of anexemplary mobile station having a user interface for replayingpreviously recorded PTT voice communications is shown. The mobilestation of FIG. 8 has a housing 802 which contains the electroniccircuitry and components shown and described in relation to FIGS. 1-2.Housing 802 of mobile station 202 includes a user interface havingvisual display 222 and keypad 232 with a plurality of keys as generallyearlier shown and described in relation to FIG. 2.

The plurality of keys of keypad 232 include a plurality of telephonedigit keys (0, 1, 2, 3, 4, 5, 6, 7, 8, 9, *, and #) as well as controlkeys including a SEND key 808 (having a telephone handset icon inscribedthereon) and an END key 810 (having a telephone handset hang-up iconinscribed thereon). SEND and END keys 808 and 810 are mechanicalswitches of the mobile station which are detectable at switch inputs ofthe mobile station. In general, SEND key 808 is used by the end user forinitiating a telephone call from mobile station 202 through the wirelessnetwork, and END key 810 is used by the end user for terminating thetelephone call. Note that both SEND and END keys 808 and 810 are carriedand exposed on a front side of housing 802.

The plurality of keys also include a PTT voice communication switch 450.In this embodiment, PTT switch 450 is located on a right hand side ofhousing 802.

When PTT switch 450 is depressed by an end user, the mobile stationinitiates a PTT voice communication through the wireless network. AfterPTT switch 450 depression, audible voice signals are received at themicrophone of the mobile station and voice signals are transmittedthrough the wireless network and heard at certain other mobile stations.Unlike traditional telephone calls, PTT voice communications arerelatively immediate and do not require the entry or selection of therecipient's telephone number.

Display 222 is used to visually display indicators for PTT voicecommunications that were previously received by and recorded by themobile station. In this example, a list 850 of three PTT voice recordindicators are displayed for review by the end user. However, anysuitable number of PTT voice record indicators may be displayed. Eachindicator in list 850 comprises a line of text. One example is a PTTvoice record indicator 852 which is representative of the other PTTvoice record indicators within list 850. As shown, PTT voice recordindicator 852 includes a PTT sequence count 854, a date stamp 856, atime stamp 858, and a sender identification 860. Note that thisinformation is merely an illustrative example of what may be provided invisual display 222 and the invention is not limited to such information.

Each PTT voice communication within a PTT session may be uniquelyidentified by PTT sequence count 854 which is indicative of the order inwhich the PTT voice communication was submitted. To obtain PTT sequencecount 854, the processor of the mobile station keeps track andincrements a counter for each next PTT voice communication received andstored for the PTT session. As shown, PTT voice record indicator 852 isthe first (“[1]”) communication of the PTT session. Data stamp 856 (Jun.4, 2004) and time stamp 858 (12:15:08) indicate the date and time,respectively, of the particular PTT voice communication. Thisinformation may be derived from existing applications at the mobilestation or, alternatively, may be received during the PTT voicecommunication in a control message. Sender identification 860 uniquelyidentifies the sender or end user (mobile station) of the PTT voicecommunication. In this embodiment, sender identification 860 is atelephone number (“519-555-1212”) of the sending mobile station. Senderidentification 860 is received in a control message from the sendingmobile station just before the PTT voice communication from the mobilestation.

The user interface of FIG. 3 also includes a data item selectionmechanism for use with visual display 222. The selection mechanism isused with visual display 222 for selecting and replaying the recordedPTT voice communications. In the present embodiment, the selectionmechanism of the mobile station is a scrollwheel 812. Scrollwheel 812 ispositioned on a right hand side of housing 302. Scrollwheel 812generally includes a circular disc which is rotable about a fixed axisof housing 802, and may be rotated by the end user's index finger orthumb. See the directions indicated by a rotation arrow 814 ofscrollwheel 812 shown in FIG. 8. An upwards rotation of scrollwheel 812causes an upwards scrolling such that data items visual display 222.Similarly, a downwards rotation of scrollwheel 812 causes a downwardsscrolling such that visual display 222 presents viewing of a lowerportion of the information. Note also that scrollwheel 812 is mountedalong a fixed linear axis such that the end user can depress scrollwheel812 inwards toward housing 812 (e.g. with the end user's index finger orthumb) for selection of data items. See the directions indicated by anarrow 816 of scrollwheel 812.

A more detailed mechanism for scrollwheel 812 is now described inrelation to FIGS. 9 and 10. Scrollwheel 812 of FIGS. 9-10 is shownconnected to and rotatable about a body assembly 910. Body assembly 910may be connected to or be part of a slide assembly 920. Slide assembly920 allows the entirety of scrollwheel 812 and body assembly 910 to movefreely laterally 816 with respect to the handheld device. Lateralscrollwheel movement 816 is defined as movement along a plane normal tothe rotational axis of scrollwheel 812. To control this lateral movement812, slide assembly 920 may be connected to a control mechanism such asa cam mechanism 930 with a cam 931, or alternatively a level mechanism,a solenoid mechanism, or some other actuating means. Cam mechanism 930is connected to a cam controller 940 (FIG. 10 only) responsible forcontrolling a lateral position of scrollwheel 812. As cam 931 connectedto cam mechanism 930 and slide assembly 920 moves, scrollwheel 812 andbody assembly 910 accordingly move laterally. Such lateral movementinwards toward the housing is detectable by the processor of the mobilestation as a switch input (actuation or depression of the scrollwheelkey).

Although scrollwheel 812 of FIGS. 3, 9, and 10 has been shown anddescribed as the preferred mechanism for use in viewing and selectingvisually displayed information, any suitable viewing/selection mechanismmay be utilized for the present user interface techniques to bedescribed, such as UP and DOWN keys, a mouse and cursor mechanism, or atouch screen display mechanism.

FIG. 6 is a flowchart for describing a method of automatically recordingPTT voice communications for replay in a mobile station. This method isperformed by a mobile station within the context described above inrelation to FIGS. 1-5 and 8-10. In addition, the method may be embodiedin a computer program product which includes a storage medium (e.g.computer disk or memory) and computer instructions stored in the storagemedium. These computer instructions are performed by one or moreprocessors of the mobile station (e.g. microprocessor, DSP, etc.). Inthe description that follows, the flowchart of FIG. 6 will be describedin combination with the components of FIGS. 4-5.

Beginning at a start block 602 of FIG. 6, a processor of the mobilestation identifies whether a PTT key message has been received throughthe wireless transceiver (step 604 of FIG. 6). A PTT key message isassociated with a PTT press of the sending mobile station in thewireless network and signifies a beginning of a PTT voice communication.If the PTT key message has not yet been received, the processorcontinues to monitor for PTT key messages. If a PTT key message has beenreceived at step 604, an incoming PTT voice communication from thesending mobile station is expected to follow. The processor receives,through the wireless transceiver, a sender identification from themobile station which will be transmitting the PTT voice communication(step 606 of FIG. 6). The sender identification uniquely identifies themobile station and may be a telephone number, an IP address, or a directconnect ID, as examples. The processor causes its voice and audiocircuits to be enabled (step 608). The voice and audio circuits mayinclude voice decompressor 406, CODEC 404, audio circuit 402, andspeaker 234 (FIG. 4).

The processor then identifies whether recording for PTT voicecommunications is enabled for the mobile station (step 610 of FIG. 6).The recording feature may be an option and may be selectable andsettable by a service provider or end user at the user interface of themobile station. The recording feature may be indicated as a saved “bitflag” in memory of the mobile station. If the processor identifies thatthe recording feature is not enabled as tested in step 610, thenconventional PTT voice communication processing is performed. In thiscase, voice data for the PTT voice communication is received through thewireless transceiver (step 612 of FIG. 6). This voice data is processedso that audible voice signals are heard from the speaker of the mobilestation. For example, RF signals carrying the voice data may beprocessed by receiver 212, channel decoder and demodulator 408, voicedecompressor 406, CODEC 404, and audio circuit 402 so that audible voicesignals are delivered through speaker 234 of FIG. 4.

During the receipt and processing of this voice data, the processormonitors whether a PTT dekey message is received (step 614 of FIG. 6). APTT dekey message corresponds to a PTT release of the sending mobilestation and signifies an end of the PTT voice communication. If the PTTdekey message has not yet been received at step 614, the voice datacontinues to be received and processed by the mobile station. If the PTTdekey is received at step 614, then the processor causes the voice andaudio circuits to be disabled (step 616 of FIG. 6) and ceases anyfurther voice processing. The method repeats again starting at step 604.

If the processor identifies that the recording feature is enabled astested in step 610, however, conventional PTT voice communicationprocessing and recording of the voice data in memory are performed. Tobegin, the processor performs a switching operation so that the upcomingvoice data of the PTT voice communication will be stored in memory (step618 of FIG. 6). Preferably, memory 412 of FIGS. 4-5 is utilized. Theprocessor also identifies the sender identification (previouslyreceived) and stores it in memory in association with the upcoming PTTvoice data (step 620 and FIG. 6). Referring to FIG. 5, a senderidentification table 550 may be stored in memory for associating senderidentifications (e.g. telephone numbers) with corresponding PTT voicecommunications. Sender identification table 550 in FIG. 5 is shown tohave four sender identifications (which correspond to four recorded PTTvoice communications) including a sender identification A 570 and asender identification B 572. Next, a PTT sequence counter, a date stamp,and/or time stamp, as well as any other pertinent information, may alsobe stored in association with the voice data as well (step 622 of FIG.6). This information may be received through the wireless transceiverfrom the sending mobile station or the wireless network, or obtainedthrough applications running in the receiving mobile station.

The processor then sets a start marker at the current input pointeraddress to mark the beginning of the PTT voice communication (step 624of FIG. 6). See start marker 502 (“A”) of FIG. 5, for example. Next, thevoice data for the PTT voice communication is received through thewireless transceiver (step 626 of FIG. 6). The voice data is processedso that audible voice signals are heard through the speaker of themobile station. In particular, RF signals carrying the voice data may beprocessed through receiver 212, channel decoder and demodulator 408,voice decompressor 406, CODEC 404, and audio circuit 402 of FIG. 4.Advantageously, the voice data of the PTT voice communication is alsosimultaneously saved in memory (step 628 of FIG. 6). Preferably, thecircular buffer memory 412 of FIGS. 4-5 is utilized for the recording ofthe PTT voice data as previously described. The first voice data item ofthe PTT voice communication is stored at the current location of theinput pointer address, and subsequent voice data items are stored at thenext available locations in sequence.

During the continuous receipt, processing, and storage of voice data ofthe PTT voice communication, the processor monitors whether a PTT dekeymessage has been received (step 630 of FIG. 6). If the PTT dekey messagehas not yet been received as tested in step 630, the voice datacontinues to be received, processed, and stored in the memory in asequential fashion. If the PTT dekey is received as tested in step 630,however, then the processor sets an end marker at the current inputpointer address (step 632 of FIG. 6). The end marker signifies the endof the PTT voice communication. See end marker 504 (“A”) of FIG. 5, forexample. The processor then sets the switches so that the voice datastorage is terminated (step 634 of FIG. 6). The voice and audio circuitsare disabled by the processor (step 616 of FIG. 6).

The storing method may repeat again starting at step 604 for subsequentPTT voice communications. These subsequent PTT voice communications aredistinguished in the memory by start and end markers and senderidentifications that are different from the initial PTT voicecommunication. Since a circular buffer memory is utilized (FIG. 5),older PTT voice communications get written over by newer PTT voicecommunications. Preferably, the visual displaying of information shownand described in relation to FIG. 8 is limited to those stored PTT voicecommunications that have not been overwritten. That is, if a PTT voicecommunication gets overwritten by a new incoming PTT voicecommunication, then it will not appear in the list of PTT voiceindicators. When voice data is overwritten, the processor deletes thestart and end markers, the sender identification, and other informationassociated with the PTT voice communication, and does not cause theassociated PTT voice indicator to be displayed in the visual display.

The mobile station may also save its own PTT voice communications in itsmemory in a similar manner, in sequence along with the PTT voicecommunications received through its receiver. This option provides amore complete history of PTT voice communications stored in memory. Inthis case, steps 604 and 630 of FIG. 6 correspond to detecting PTTbutton depressions and PTT button releases, respectively, at the userinterface of the mobile station. Upon PTT button depression, theprocessor causes the voice data of the PTT voice transmission to bestored in the memory simultaneously with its transmission. This voicedata may be voice compressed data from an output of its voice compressor(i.e. the same form as the received PTT voice communications). Theprocessor also sets the identification of the PTT voice communication asthe mobile station's ID, the date stamp, the time stamp, etc., asappropriate.

FIG. 7 is a flowchart for describing a method of providing replay ofpreviously recorded PTT voice communications in the mobile station. Therecorded PTT voice communications may be those stored in accordance withthe previously described flowchart of FIG. 6. This method is performedby a mobile station within the context described above in relation toFIGS. 1-5 and 8-10. In addition, the method may be embodied in acomputer program product which includes a storage medium (e.g. computerdisk or memory) and computer instructions stored in the storage medium.These computer instructions are performed by one or more processors ofthe mobile station (e.g. microprocessor, DSP, etc.). In the descriptionthat follows, the flowchart of FIG. 7 will be described in combinationwith the components of FIGS. 4-5 and 8.

Beginning at a start block 702 of FIG. 7, the processor of the mobilestation causes a list of stored PTT voice indicators to be displayed inits visual display (step 704 of FIG. 7). Preferably, each stored PTTvoice communication is associated with a sender identification and otherinformation which is displayed along with the stored PTT voiceindicator. Most preferably, the information and format shown anddescribed in relation to FIG. 8 is utilized. Back to FIG. 7, theprocessor then monitors user input signals at the user interface. Theprocessor identifies whether an “exit” selection has been detected atthe user interface (step 706 of FIG. 7). If so, the processor causesother processing to occur (step 750 of FIG. 7) which is unrelated to thepresent application. The processor also identifies whether a PTT replayselection has been selected at the user interface (step 708 of FIG. 7).If not, the processor continues monitoring for user inputs at the userinterface. Preferably, the selection at the user interface utilizes thetechniques previously described in relation to FIG. 8.

If the processor identifies that a PTT replay has been selected at step708, then the processor causes a switching operation to be performed sothat a PTT voice communication stored in the memory can be played orreplayed (step 710 of FIG. 7). The processor identifies the PTT voiceindicator selected by the end user, and sets the output pointer addressto point to the memory location associated with the start marker of thePTT voice communication (step 712 of FIG. 7). The processor also enablesthe voice and audio circuits for playing the selected PTT voicecommunication (step 714 of FIG. 7). The voice and audio circuits mayinclude voice decompressor 406, CODEC 404, and audio circuit 402 of FIG.4. For playing the voice signals, the processor repeatedly increments(or decrements) the output pointer address to retrieve each next voicedata item from the memory for processing such that audible voice signalsare heard from the speaker (step 716 of FIG. 7). Each voice data itemmay be compressed voice data which is processed by voice compressor 406,CODEC 404, and audio circuit 402 of FIG. 4. Such operation is performedfor all stored voice data of the PTT voice communication until theoutput pointer address matches the end marker (step 718 of FIG. 7). Oncethe end marker is reached, the PTT voice communication has ended. Theprocessor disables the voice and audio circuits (step 720) and causesthe switches to be set so as to terminate the retrieval of voice data(step 722 of FIG. 7). The method may repeat again for any subsequent PTTvoice replays.

Advantageously, PTT voice communications that are missed (e.g.especially the first PTT voice communication of a PTT session) may bereplayed by an end user. The recording of PTT voice is performedautomatically by the mobile station without the need for effort orinvolvement by the end user. Using PTT key and dekey messages forrecording initiation and recording termination, respectively, conservesmemory space as compared to continuous recording over a PTT session.Note that recording of voice is not performed (or performedautomatically) for cellular telephone calls, which can be answered orunanswered after an audible or tactile alert at the mobile station.

Final Comments. As described herein, methods and apparatus forautomatically recording Push-To-Talk (PTT) voice communications forreplay in a mobile station have been described. In one illustrativeexample, a mobile station includes a wireless transceiver which operateswith a wireless communication network; a processor; memory coupled tothe processor; and a user interface which includes a Push-To-Talk (PTT)switch for transmitting a PTT voice communication through the wirelesstransceiver, a PTT replay switch for replaying a PTT voice communicationpreviously received through the wireless transceiver which is stored inthe memory, and a speaker for outputting audible voice signals. Thewireless transceiver is operative to receive a PTT key message; receivevoice data of a PTT voice communication following the PTT key message;and receive a PTT dekey message following the voice data. The processoris operative to cause the voice data of the PTT voice communication tobe recorded in the memory based on receiving the PTT key message, andcause the recording of voice data of the PTT voice communication to beterminated based on receiving the PTT dekey message. Subsequently, inresponse to detecting a user actuation of the PTT replay switch, theprocessor causes the voice data of the PTT voice communication to beretrieved from the memory and audible voice signals corresponding to thevoice data to be output from the speaker.

A wireless communication system of the present application includes awireless communication network; a Push-to-talk (PTT) server coupled inthe wireless network; and one or more mobile stations which operate inthe wireless communication network. Each mobile station includes awireless transceiver which operates with the wireless communicationnetwork; one or more processors; memory coupled to the one or moreprocessors; and a user interface which includes a Push-To-Talk (PTT)switch for transmitting a PTT voice communication through the wirelesstransceiver, a PTT replay switch for replaying a PTT voice communicationpreviously received through the wireless transceiver and stored in thememory, and a speaker for outputting audible voice signals. The wirelesstransceiver is operative to receive a PTT key message; receive voicedata of a PTT voice communication following the PTT key message; andreceive a PTT dekey message following the PTT voice communication. Theone or more processors are operative to cause the voice data of the PTTvoice communication to be recorded in the memory based on receiving thePTT key message; and cause the recording of voice data of the PTT voicecommunication to be terminated based on receiving the PTT dekey message.

A method of the present application includes the steps of receiving aPTT key message from a mobile station through a wireless communicationnetwork; receiving voice data of a PTT voice communication following thePTT key message; causing the voice data of the PTT voice communicationto be recorded in memory of the mobile station based on receiving thePTT key message; receiving a PTT dekey message from the mobile stationthrough the wireless communication network; and causing the recording ofvoice data of the PTT voice communication to be terminated based onreceiving the PTT dekey message. A computer program product of thepresent application includes a storage medium; computer instructionsstored in the storage medium; where the computer instructions areexecutable by one or more processors for performing the methodpreviously described.

The above-described embodiments of the present application are intendedto be examples only. For example, the wireless network may be an iDENnetwork which provides for PTT communications between mobile stations.Those of skill in the art may effect alterations, modifications andvariations to the particular embodiments without departing from thescope of the application. The invention described herein in the recitedclaims intends to cover and embrace all suitable changes in technology.

1. A method for a mobile station in a wireless communication network forrecording Push-To-Talk (PTT) voice communications of a PTT communicationsession, the method comprising of: receiving a PTT key message from aPush-To-Talk over Cellular (PoC) server, the PTT key message beingindicative of an incoming PTT voice communication; receiving from thePoC server a sender identification associated with the incoming PTTvoice communication; receiving the incoming PTT voice communication fromthe PoC server, as indicated by the PTT key message; and causing the PTTvoice communication to be recorded in the memory of the mobile stationin association with the sender information.
 2. The method of claim 1,wherein the PTT voice communication is only recorded if a userselectable setting in the mobile station indicates that PTT recording isenabled.
 3. The method of claim 1, further comprising: storing thesender identification in the memory of the mobile device.
 4. The methodof claim 1, wherein the sender identification comprises a telephonenumber.
 5. The method of claim 1, further comprising: identifying a timestamp for the PTT voice communication; and wherein the PTT voicecommunication is recorded in the memory of the mobile station inassociation with the identified timestamp.
 6. The method of claim 1,further comprising: identifying a date stamp for the PTT voicecommunication; and wherein the PTT voice communication is recorded inthe memory of the mobile station in association with the identified datestamp.
 7. The method of claim 1, wherein the PTT recording act isperformed for each one of a plurality of PTT voice communicationsessions, and wherein the PTT key message comprises a first key message,the incoming PTT voice comprises a first incoming PTT voicecommunication and the sender information comprises a first senderinformation, the method further comprising: receiving a second PTT keymessage from the Push-to-talk over Cellular (PoC) server, the second PTTkey message indicative of a second incoming PTT voice communication;receiving from the PoC server a second sender identification associatedwith the second incoming PTT voice communication; and causing the secondincoming PTT voice communication to be recorded in the memory of themobile station in association with the second sender information.
 8. Themethod of claim 1, further compromising storing a sender identificationtable in memory of the mobile device for respectively associating firstand second incoming PTT voice communications with first and secondsender identifications.
 9. The method of claim 1, which is performed bycomputer instructions stored in a computer readable medium andexecutable by a processor of the mobile station.
 10. A mobile station,comprising: a wireless transceiver which operates with a wirelesscommunication network; one or more processors; memory coupled to the oneor more processors; a user interface which includes: a Push-To-Talk(PTT) switch for transmitting a PTT voice communication through thewireless transceiver; a PTT replay switch for replaying a PTT voicecommunication previously received through the wireless transceiver andstored in the memory; a speaker for outputting audible voice signals;the one or more processors being operative to: receive, via the wirelesstransceiver, a PTT key message from a Push-To-Talk over Cellular (PoC)server, the PTT key message being indicative of an incoming PTT voicecommunication; receive, via the wireless transceiver, from the PoCserver, a sender identification associated with the incoming PTT voicecommunication; receive, via the wireless transceiver, the incoming PTTvoice communication from the PoC server, as indicated by the PTT keymessage; and cause the PTT voice communication to be recorded in thememory of the mobile station in association with the sender information.11. The mobile station of claim 10, wherein the PTT voice communicationis only recorded if a user selectable setting in the mobile stationindicates that PTT recording is enabled.
 12. The mobile station of claim10, wherein the one or more processors are further operative to: storethe sender identification in the memory.
 13. The mobile station of claim10, wherein the sender identification comprises a telephone number. 14.The mobile station of claim 10, wherein the one or more processors arefurther operative to: identify a time stamp for the PTT voicecommunication; and wherein the PTT voice communication is recorded inthe memory of the mobile station in association with the identifiedtimestamp.
 15. The mobile station of claim 10, wherein the one or moreprocessors are further operative to: identify a date stamp for the PTTvoice communication; and wherein the PTT voice communication is recordedin the memory of the mobile station in association with the identifieddate stamp.
 16. The mobile station of claim 10, wherein the PTTrecording is performed for each one of a plurality of PTT voicecommunication sessions, and wherein the PTT key message comprises afirst key message, the incoming PTT voice comprises a first incoming PTTvoice communication and the sender information comprises a first senderinformation, wherein the one or more processors are further operativeto:: receiving a second PTT key message from the Push-to-talk overCellular (PoC) server, the second PTT key message indicative of a secondincoming PTT voice communication; receiving from the PoC server a secondsender identification associated with the second incoming PTT voicecommunication; and causing the second incoming PTT voice communicationto be recorded in the memory of the mobile station in association withthe second sender information.
 17. The mobile station of claim 10,wherein the one or more processors are further operative to store asender identification table in memory of the mobile device forrespectively associating first and second incoming PTT voicecommunications with first and second sender identifications.
 18. Awireless communication system, comprising: a wireless communicationnetwork; a Push-to-talk (PTT) server coupled in the wireless network;one or more mobile stations which operate in the wireless communicationnetwork, each mobile station including: a Push-To-Talk (PTT) switch fortransmitting a PTT voice communication through the wireless transceiver;a PTT replay switch for replaying a PTT voice communication previouslyreceived through the wireless transceiver and stored in the memory; aspeaker for outputting audible voice signals; each mobile station beingoperative to: receive a PTT key message from the Push-To-Talk overCellular (PoC) sever, the PTT key message being indicative of anincoming PTT voice communication; receive from the PoC server a senderidentification associated with the incoming PTT voice communication;receive the incoming PTT voice communication from the PoC server, asindicated by the PTT key message; and cause the PTT voice communicationto be recorded in memory of the mobile station in association with thesender information.
 19. The wireless communication system of claim 18,wherein the PTT voice communication is only recorded if a userselectable setting in the mobile station indicates that PTT recording isenabled
 20. The wireless communication system of claim 18, wherein eachmobile station is further operative to: store the sender identificationin the memory.
 21. The wireless communication system of claim 18,wherein the sender identification comprises a telephone number.
 22. Thewireless communication system of claim 18, wherein each mobile stationis further operative to: identify a time stamp for the PTT voicecommunication; and wherein the PTT voice communication is recorded inthe memory of the mobile station in association with the identifiedtimestamp.
 23. The wireless communication system of claim 18, whereineach mobile station is further operative to: identify a date stamp forthe PTT voice communication; and wherein the PTT voice communication isrecorded in the memory of the mobile station in association with theidentified date stamp.
 24. The wireless communication system of claim18, wherein the PTT recording is performed for each one of a pluralityof PTT voice communication sessions, and wherein the PTT key messagecomprises a first key message, the incoming PTT voice comprises a firstincoming PTT voice communication and the sender information comprises afirst sender information, wherein each mobile station is furtheroperative to: receiving a second PTT key message from the Push-to-talkover Cellular (PoC) server, the second PTT key message indicative of asecond incoming PTT voice communication; receiving from the PoC server asecond sender identification associated with the second incoming PTTvoice communication; and causing the second incoming PTT voicecommunication to be recorded in the memory of the mobile station inassociation with the second sender information.
 25. The wirelesscommunication system of claim 18, wherein each mobile station is furtheroperative to store a sender identification table in memory of the mobiledevice for respectively associating first and second incoming PTT voicecommunications with first and second sender identifications.